When Many Adventurers Do One Thing

Sometimes the efforts of many add neatly, as when many arms try to lift a gate.

Other times, they add imperfectly, as when many eyes try to sight or many ears to hear. It's a mix of varying factors: what's being sensed "out there" and the individual's attention. The individual can only contribute so much.

Other times, additional hands are useless, as when picking a lock, or downright counterproductive, as when many people try to hide or sneak.

In a game, very few skills add neatly except for the sheer application of brute force. Those that add uselessly should be obvious. Which leaves the imperfect and the counterproductive situations to deal with.

So when adding skills imperfectly (and why not, there are diminishing returns even when opening a door because only so many people can get good leverage):

One person = one check
2-3 people = 2 checks
4-7 people = 3 checks, made by the 3 best people
8-15 = 4 checks, made by the 4 best, and so on.

Each power of 2 adds another check.

And when skills interfere - as when a large group is trying to sneak:

One person =one check
2 people = 2 checks
Up to 4 people = 3 checks, made by the 3 worst people
Up to 8 = 4 checks, made by the 4 worst, and so on.
Up to 16 = 5 checks and so on.

Failure by any one means noise is made or they can be seen.

A Simple Chase Rule

Following on the previous post about random movement rates and chases, here's the simplest chase rule I can come up with:

Just before moving, a character may choose to give up its regular movement rate and instead move d6 for every 3 points of movement, plus 1 for every leftover point. A movement rate of 12 becomes 4d6, for example, and a move of 10 becomes 3d6+1. This move is rerolled on every round it is used.

Cue "Yakety Sax."

This does a number of things.

1. It makes chases exciting in a simple and traditional way.

2. In normal tactical combat movement, there is seldom going to be a reason to delay the game by rolling movement instead of using the reliable rate. As I noted last time, the normal move rate usually will be enough to do whatever maneuvering is needed once sides have closed. If that's so, then you don't want to take the chance of a low roll ruining it.

3. The dice will normally only be used if speed is of the essence - charging missile weapons, racing an enemy to get to a switch, or just plain chases. Why? Because the average roll of a d6 is 3.5, giving a variable but overall half-point advantage over a plain predictable 3.

4. It represents switching from a more cautious to a more risky mode of movement. Good and bad rolls can  be visualized as bursts of speed or accidents.

5. It slots easily into any number of combat rules sequences by offering an option for movement, whenever and however that happens.

6. It reflects the advantage of a large pursuing party; each round, the more figures you have, the more likely someone will roll high and catch up. Outpacing a horde of 6-move kobolds with your 9-move party is no longer such a done deal! At the same time, if this gives too much unrealistic advantage to an unruly mob, you can just say (as my rules do) that you need to spend 3 movement points in order to pass through a slower figure in front. 

As simple as it is, this rule is missing a couple of things. One is the possibility for character stats and terrain to regulate such things as dodging obstacles and getting tired. These I'll cover next post.

Another is a protocol for ending the chase. With perfect visibility ahead, a chase can continue until the pursuing side catches up or gives up. If a chase is taking place across terrain already mapped by the DM - for example, a dungeon or a well-developed city - then visibility is easy to determine. Otherwise, visibility can be determined generically - 10' in thick fog, 20' in twisty city streets, 30' in deep woods, and so on.

When the chasers lose sight of their quarry and there is more than one way to go, they need to decide whether to split up, continue along one way at the risk of being entirely wrong, or give up. Those being pursued, once the chasers lose sight of them, also have the well-known cinematic option of finding some place to hide and waiting as the chase goes by. 

To guard against this, the more intelligent kind of pursuers, if numerous,  will need to leave behind a searcher each round. Somehow, they never seem to do that in the movies ...

Surprise

When two groups meet by chance in classic D&D games, there is a chance for each to surprise the other. Breaking it down, what factors might be going into this?

• Lack of awareness: One side might have lost attention - sleeping, eating, reading, sexing. One side might be blind and deaf in its environment, like a lightless swimmer under dark waters.
• Lack of concealment: One side is giving itself away - taking light into the dark, noise into the silence, laughing, gambling, brawling.
• Exceptional awareness:  One side might be waiting by the door to ambush oncomers all day and all night. One side might have ESP, or heat vision, or elven ears.
• Exceptional concealment: One side might be hiding behind a rock, on the ceiling; invisible.

The typical situation of a party going into the dungeon is gross lack of concealment, with naked lamps and clanking armor; but high vigilance; forging on into unknown territory.

The typical situation of bored watchmen is of greater concealment, but lower vigilance. Undead watchmen are more vigilant. Gambling, shouting watchmen are less concealed.

Nope. No dice roll needed.

Most surprise situations can be resolved by detailed enough setting notes about what the guards are up to, whether the vampire is stalking prey or playing the pipe organ, whether the spider is hiding in the webs or scuttling along the floor. For situations where the DM wants more spontaneity, a monster vigilance roll might be needed to see whether the monsters are in a position to ambush, or are giving away their own position. The chance to spot the ambush can be handled as a passive perception check (spotting, plus listening if the ambushers are moving). If the ambushing party has a hide skill and successfully uses it, the perception check gets more difficult.

To determine the enemy's disposition randomly, roll 1d6 for each individual, up to 5; the remaining individuals have similar profiles to the 5 rolls already made, in the order rolled.

Undisciplined groups and individuals:
1: vigilant; 2-3: distracted; 4: distracted and making noise; 5-6: asleep.

Disciplined groups and individuals: 

1: ambushing already; 2-3: vigilant; 4: distracted; 5-6: asleep (at least one member of a disciplined group of 2 or more will be vigilant)

Predators:
1-2: ambushing already; 3-4: vigilant; 5-6 asleep.

Inhuman: 

1-2: ambushing already; 3-6 vigilant.

Non-intelligent:
Vigilant to the range of their senses, unless in a situation to ambush (such as an ooze dropping from above.)

Example: Our group approaches a right turn in the passage, torches blazing. 100 feet down the corridor is an open guardroom where three undisciplined kobolds are lounging. Will the kobolds hear the clank of armor and see the reflection of light on the wall? The roll for the trio is 1, 6, 6, and the signs of the party approaching are pretty blatant, so the one vigilant kobold notices without having to roll, and scuttles over to shake and wake the other sleeping two.

This makes a much quieter noise (but can't be seen)  so I give the two party members in front a secret roll on their d6-based listen skills, one has a listen skill of 1 and the other has 2. The one with 2 rolls a 2 and hears some scuttling, faint groaning and whispering ahead and to the right. Round 1 is over.

Round 2, the party stops, hides the torch behind a shield and sends their infravision-having, non-clanking dwarf to look down the passage. The vision only goes 30' so he sees nothing but passage. His listen skill is also a bare 1, but he rolls it, so he hears some more noises of blades being drawn, buckles being buckled, and footsteps. The kobolds are arming themselves. At this point, if a party member with a fast move and a torch were to run screaming ahead, he would probably catch the two dressing kobolds, if not the vigilant one, by surprise. But no, they go cautiously. And the kobolds get one more move, unheard, to set up their ambush in the corner of the guardroom just right of where the passage comes in.

After a couple of rounds creeping down the passage in full defense mode, the party reaches the entrance of the guardroom, then state that they will swing out quickly and attack to the sides. Because they are wresting surprise back from the kobolds (at some risk to themselves!) I deny the kobolds the surprise attack they would have gotten, and normal initiative is rolled.

If the players had not shown guts like that, though, I would have judged the kobolds to be perfectly hidden behind the corner, so the front right member must make two successful rolls to "notice detail" (my proxy skill for reacting quickly to a visual stimulus) in order to deny the surprise attack prior to initiative.

The moral? Time is not always on the party's side; and the cautious approach won't always give the best results. This insight is the best cure for over-cautious party creep I know.